Apparatus for freeze drying products in small containers



ML SELIGMAN Nov. 22, 1966 APPARATUS FOR FREEZE DRYING PRODUCTS IN SMALL CONTAINERS Filed Oct. 26, 1964 "Hun. .4

I3 1) it I INVENTOR. NAM/RUE 55L m/vAA/ 3,286,356 Patented Nov. 22, 1966 United States Patent Office 3,286,366 APPARATUS FOR FREEZE DRYING PRODUCTS IN SMALL CONTAINERS Monroe Seligman, 115 The Circle-Passaic, NJ; Filed Oct. 26, 1964, Ser. No.-406,330 2 Claims. (Cl. 34-92) This invention relates to freeze drying and more particularly the method of treating a small container containing a product while maintaining a condition of freedornfrom contamination of the product and producing a rapid freeze and. sealing the 'container..after -the freeze drying process and maintaining the freedom from contamination of the product.

The prior art illustrates theuse of a single element (platen) that is used to press the stopper or cork into a plurality of containers. In the prior art there are containers that have. been, treated by heat t'o. completely sterilize the container and itsfcon'tents, however in the freeze drying art, the'cont'ent ofthe container is generally a liquid such as plasma or serum, which would be destroyed by heat. .In the freezedrying art the con.- tainer is sterilized .or cleaned prior to its'actu'al use. One of the reasonsthat a freeze dryer is used to remove the moisture "from the material or liquid to be treated is the fact that heat would destroy most of the material or liquid treated in this manner.

The object of this invention is to provide a particular process namely, freeze drying, in whichthe,product is filled into a plurality of containers that have been cleaned or sterilized, that is, the stoppers are inserted to .retain the contents free from contamination during handling. As a further step in this process, the sealed containers are mounted within a freeze dryer and cooled to a desired degree. The platen is then positioned in a hold down position over the stoppers and the pressure within the freeze dryer is reduced. The platen is then moved rapidly to a release position allowing a predetermined distance from the stoppers to pop. The stoppers will pop because of a greater pressure within the containers with a vacuum or reduced pressure outside the containers.

When the stoppers pop this permits the exposure of the drying, the platen shall be moved in a direction to reinsert the stoppers into their sealed relationship with the container and each container remains vacuum sealed.

The vacuum or reduced pressure surrounding the containers shall also be released.

Further objects of this invention shall be apparent by reference to the accompanying detailed description and the drawings in which FIG. 1 illustrates a cross sectional view of a freeze dryer, and

FIG. 2 illustrates a cross sectional view of a further embodiment.

Referring to the drawings there is provided a freeze dryer 10 having a cover 11. shown) is connected to the freeze dryer 10 so that it may be evacuated when the cover 11 has been positioned in a sealed relationship as illustrated. The freeze dryer A vacuum source 12 (not is provided with a cooling coil and condenser 8 having,

The-freeze dryer is also provided with a movable platen 14 that is retained in the raised position as illustrated by a plurality of springs 15 and restricted in its upward movement by a plurality of stop nuts 13. The platen is also provided with an expandable air cylinder 16 such as the bellows illustrated. The upper limit of the bellows is retained by a structural element 17 which is affixed to the container 10 and may be, further retained by a plurality of bolts 18 by providing a plurality of nuts 19 to position element 17 as illustrated... An air supply 20 is connected to the bellows 16 through a port 21 using a valve 22. The pressuredeveloped within the bellows to provide a downward thrust may vary as required according to the number of bottles and stoppers or according to their size. In use a plurality of containers such as bottles 25 may be stackedon the bottom of the container 10. When the bottles have been properly filled with the contents to be treated, the stoppers are inserted and they are then stacked into the freeze dryer. However in the process of freeze drying, the freeze dryer 10 is open initially permitting easy stacking of bottles 25 with their stoppers sealing the contents. Thus the freeze dryer 10 may be closed after loading or stacking bottles 25. The cover 11 is positioned as shown in FIG. 1. Any type of cooling of bottles 25 may be employed, however in thisjinsta'nce the bottles are cooled to freeze the contents by circulating the atmosphere surrounding the bottles,

for example, by utilizing a condenser and refrigerant coil 8 within the freeze drying chamber and providing a fan 9 behind the refrigerant coil. The fan 9 is supported on a shaft 9' that is driven by a motor (not shown). The refrigerant coil is connected by pipes 8' to a' refrigerant source (not shown). Thus the chamber within the freezing device 10 may be cooled to thus produce the desired cooling around the containers 25. The container 10 may also include a conduction base plate 10' on which all containers are mounted. The base plate 10' may also be provided with a heater element 7 so that heat may be readily conducted through base plate 10' to the base of each container 25. The heating element 7 is in turn connected through a switch S and variable resistor control V to a battery B to thus control the degree of potential to the heater and thus control the degree of heat furnished to the base of each container 25. The heater 7 is only utilized to prevent cooling containers 25 to a greater degree than desired and thus maintaining the shell freeze within containers 25 at approximately the freezing temperature. The bottles are subject to the lowering of their temperature to a predetermined point (just about freezing temperature of the contents of the bottle). This may be noted by a thermometer 6. With the initial freeze of the contents of bottles 25, the platen is lowered to the dotted position and retained in this position. The vacuum source 12 is turned on (valve 12') to partially evacuate the air within the freeze dryer. As the pressure within container 10 drops to or approaches a difference of one atmosphere (between outside and inside) the platen is raised by suddenly releasing the pressure within the expandable cylinder 16. The air pressure within bottles 25 being greater than the pressure surrounding the bottles causes the stoppers 26 to pop. The platen 14 may be in a predetermined position above bottles 25 to thus prevent the stoppers from popping to the extent that they leave the neck of the bottle. Rather the stopper 26 pops sufficiently to allow the exposure of the contents of the bottles 25 to the conditions existing within the freeze dryer. After the contents of bottles 25 have all been dried, that is, after the water vapor has been released from the frozen content to the degree desired, valve 22 may be actuated or opened permitting the air pressure from 20 to expand bellows 16 moving the platen 14 downward to reinsert the stoppers 26. When stoppers 26 have been sealed in the containers 25 the vacuum valve 12' may be closed. The vacuum is then released by a release valve 12". A release valve 22' may then be opened releasing pressure from the bellows 16 and allowing springs 15 to raise the platen 14 to the position as illustrated in FIG. 1. The cover 11 may then be removed and the containers 25 may be removed from the Vacuum chamber 10.

Referring to FIG. 2 there is illustrated a similar type of freeze dryer also provided with a vacuum source 12 and valve 12. The cover 11 for the freeze drying container 10 is provided with a single aperture 29 and a shaft 30 is mounted therein, the lower end of shaft 30 supporting a platen 14 and the upper end of shaft 30 provided with a cam 31. Cam 31 is in turn pivotally supported on a shaft 32 to be retained in contact with the upper end of shaft 30. Shaft 30 is supported in a pair of bearing supports 33 that are affixed to the cover 11. A handle or bar 34 is afiixed to cam 31 to permit moving it as illustrated in dotted lines. Thus the platen 14 may be moved downward or upward by dropping or lifting the handle 34. In this embodiment a plurality of containers 25 are provided with stoppers 26 similar to the previous embodiment. However, in another embodiment, the platen 14 will not be provided with a stop 13 and the cam 31 has a greater lift in this instance. The stoppers 26 must be of a design that will permit the stopper to pop to release the positive pressure from within the bottle 25 but the stopper must be providedwith means to be retained by the bottle, that is, the neck of the stopper should be longer and there should be means to prevent the stopper from being totally popped. Thus the platen 14 may be raised without worrying about a predetermined position. After the contents of the container 10 have been evacuated and the bottles 25 have been treated, that is, by the freeze drying process, handle 34 may be rotated to press platen 14 downward to reinsert the stoppers 26 that have popped open thus rescaling stoppers 26 to complete the process. The vacuum valve 12' may then be closed and the release valve 12" opened and the cover 11 removed and the containers 25 may be removed from container 10.

A further embodiment of this invention is to utilize this device (FIGS. 1 or 2) for other than freeze drying. For example, when a plurality of bottles have been properly filled with the contents to be treated the stoppers are inserted to retain the contents contaminant free and they are then stacked into the device 10. The dryer 10 may be closed by placing the cover in position as shown in the figures. The platen is lowered to the dotted position to retain the stoppers closed. The vacuum source 12 is turned on by valve 12' to partially evacuate the air within the dryer. As the pressure within the container drops to or approaches a difference of one atmosphere, the platen is raised by suddenly releasing. The air pressure wi-thin bottles 25 being greater than the air pressure surrounding the bottles causes the stoppers 26 to pop. As in the previous embodiment, platen 14 may be in a predetermined position above bottles 25 to thus prevent the stoppers from popping to the extent that they leave the neck of the bottle. However the stoppers are sufficiently popped to allow the exposure of the contents of the bottles to treatment within the dryer. The heater 7 is energized and the heat from the heater 7 is conducted through base plate 10' to heat bottles 25 and their contents. With the stoppers open, there is provided a dry heat to dry the contents while maintaining the bottles contaminant free within the'dryer. When the contents have been thoroughly dried, platen 14 may be moved downward so that the stoppers 26 are reinserted and the valve 12 closed and the valve 12" opened thus re-entering atmospheric pressure within the container to permit removing cover 11 and thus removing the bottles 25 for further handling.

A still further embodiment of this invention is to utilize the device (FIGS. 1 and'2) for other than freeze drying or simply drying by heat. For example, when a plurality of bottles have been properly filled with the contents to be treated, the stoppers are inserted to retain the contents contaminant free and they are then stacked into the device 10. The dryer 10 may be closed by placing the cover in position as shown in the figures. The platen is lowered to the dotted position to retain the stoppers closed. The vacuum source 12 is turned on by valve 12' to partially evacuate the air within the dryer. As the pressure within the container drops to or approaches a difference of one atmosphere, the valve 12' is closed. The platen is raised by suddenly releasing. The air pressure within the bottles 25 being greater than the air pressure surrounding the bottles causes the stoppers 26 to pop. As in the previous embodiment platen 14 may be in a predetermined position above bottles 25 to thus prevent the stoppers from popping to the extent that they leave the neck of the bottles. However the stoppers are sufficiently popped to allow :the exposure of the contents of the bottles to treatment within the device 10. In this embodiment a treating medium such as gas may be utilized for treating the contents of the bottles. Thus the gas to be utilized may be connected to the pipe leading to valve 12" and valve 12" opened thus introducing the gas into the chamber of device 10. The gas will pass through the open stoppers treating the contents of the bottles 25 and upon completion of the treatment, the valve 12" is closed and the valve 12' is opened to evacuate the gas from the vacuum chamber. The platen is then moved downward to reinsert stoppers 26. Valve 12' is then closed; the gas charging device is disconnected and valve 12" is opened to allow the air to enter the vacuum chamber. The cover 11 may then be removed to permit removing bottles 25 for further handling. Although a gas has been specified for treating the contents of the bottles, it is to be understood that any fluid such as a liquid may also be similarly used. Further, although the sealing of the stoppers 26 has been described as affected under vacuum, the sealing of the stoppers, that is the re-inserting of the stoppers, may be with or without vacuum according to the requirement of the contents of the bottles.

Although the containers have been illustrated as hottles with corks or stoppers 26, the contain rs may take other forms and the stoppers may take other forms as long as the stopper and container are utilized for a treating process. It is to be noted that the platen provided for preventing the escape of stoppers from the containers is also the means of reinserting the stoppers and the positioning of the platen may vary according to the desired travel of the stopper or as in another embodiment, it may travel to a greater degree due to the stopper having an inherent ability to remain with the bottle after it has popped. The platen may be solid or may be perforated as desired without departing from the spirit of this invention and although the operating means for the platen has been illustrated as an air actuated element such as a bellows, it may be provided in any other form such as a piston and cylinder or it may be as a cam element as illustrated in FIG. 2 without departing from the spirit of this invention and this invention shall be limited only by the appended claims.

What is claimed is:

1. In a lyophilizing apparatus, in combination an enclosed box-like container utilized as a freeze dryer, said box-like container having a fiat base or floor to receive a plurality of bottle shaped containers and their contents in nested abutting relationship in which all containers are identical in size and in which each container is provided with an open neck into which an elongated stopper is inserted, said box-like container provided with a cover to seal said freeze dryer, a movable platen within said freeze dryer and mounted above said floor and parallel thereto, a cooling coil and condenser within said freeze dryer, said cooling coil and condenser connected to a refrigerant system, a fan mounted within said freeze dryer to move the internal atmosphere, a heating element mounted within said freeze dryer and in the floor of said container to provide heat by conduction to said bottle shaped containers when desired, said movable platen resiliently mounted and provided with stops to limit its upward movement, means to partially evacuate said freeze dryer and partially pop said stoppers from said bottle shaped containers, means to freeze dry the contents of said bottle shaped containers, and means ,to lower said platen and return all stoppers to a sealed position in each container.

2. In a lyophilizing apparatus, in combination an enclosed box-like container utilized as a freeze dryer, said box-like container having a flat base or floor to receive a plurality of bottle shaped containers and their contents in nested abutting relationship in which all containers are identical in height and in which each container is provided with an open neck into which an elongated stopper is inserted, said box-like container provided with a cover to seal said freeze dryer, a movable platen within said freezer dryer and mounted above said floor and parallel thereto, a cooling coil and condenser operatively connected to said freeze dryer, said cooling coil and condenser connected to a refrigerant system, said movable platen resiliently mounted and provided With stops to limit its upward movement, means to partially evacuate said freeze dryer and partially pop said stoppers from said bottle shaped containers, means to freeze dry the contents of said bottle shaped containers, and means to lower said platen and return all stoppers to a sealed position in each container.

References Cited by the Examiner UNITED STATES PATENTS 649,012 5/ 1900 Tapscott 53-102 671,930 4/1901 Leffingwell 53102 2,353,986 7/1944 Barr 345 2,803,888 8/1957 Cerletti 34-5 WILLIAM J. WYE, Primary Examiner. 

1. IN A LYOPHILIZING APPARATUS, IN COMBINATION AN ENCLOSED BOX-LIKE CONTAINER UTILIZED AS A FREEZE DRYER, SAID BOX-LIKE CONTAINER HAVING A FLAT BASE OR FLOOR TO RECEIVE A PLURALITY OF BOTTLE SHAPED CONTAINERS AND THEIR CONTENTS IN NESTED ABUTTING RELATIONSIP IN WHICH ALL CONTAINERS ARE IDENTICAL IN SIZE AND IN WHICH EACH CONTAINER IS PROVIDED WITH AN OPEN NECK INTO WHICH AN ELONGATED STOPPER IN INSERTED, SAID BOX-LIKE CONTAINER PROVIDED WITH A COVER TO SEAL SAID FREEZE DRYER, A MOVABLE PLATEN WITHIN SAID FREEZE DRYER AND MOUNTED ABOVE SAID FLOOR AND PARALLEL THERETO, A COOLING COIL AND CONDENSER WITHIN SAID FREEZE DRYER, SAID COOLING COIL AND CONDENSER CONNECTED TO A REFRIGERANT SYSTEM, A FAN MOUNTED WITHIN SAID FREEZE DRYER TO MOVE THE INTERNAL ATMOSPHERE, A HEATING ELEMENT MOUNTED WITHIN SAID FREEZE DRYER AND IN THE FLOOR OF SAID CONTAINER TO PROVIDE HEAT BY CONDUCTIOON TO SAID BOTTLE SHAPED CONTAINERS WHEN DESIRED, SAID MOVABLE PLATEN RESILIENTLY MOUNTED AND PROVIDED WITH STOPS TO LIMIT ITS UPWARD MOVEMENT, MEANS TO PARTIALLY EVACUATE SAID FREEZE DRYER AND PARTICALLY POP SAID STOPPERS FROM SAID BOTTLE SHAPED CONTAINERS, MEANS TO FREEZE DRY THE CONTENTS OF SAID BOTTLE SHAPED CONTAINERS, AND MEANS TO LOWER SAID PLATEN AND RETURN ALL STOPPERS TO A SEALED POSITION IN EACH CONTAINER. 